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Diffstat (limited to 'src/lib/nsas/nameserver_address_store.cc')
-rw-r--r-- | src/lib/nsas/nameserver_address_store.cc | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/src/lib/nsas/nameserver_address_store.cc b/src/lib/nsas/nameserver_address_store.cc new file mode 100644 index 0000000000..5c79106dfd --- /dev/null +++ b/src/lib/nsas/nameserver_address_store.cc @@ -0,0 +1,96 @@ +// Copyright (C) 2010 Internet Systems Consortium, Inc. ("ISC") +// +// Permission to use, copy, modify, and/or distribute this software for any +// purpose with or without fee is hereby granted, provided that the above +// copyright notice and this permission notice appear in all copies. +// +// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH +// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY +// AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, +// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM +// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE +// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR +// PERFORMANCE OF THIS SOFTWARE. + +// $Id$ + +#include <boost/thread.hpp> +#include <boost/shared_ptr.hpp> +#include <boost/foreach.hpp> + +#include <config.h> +#include <dns/rdataclass.h> + +#include "hash_table.h" +#include "lru_list.h" +#include "hash_deleter.h" +#include "nsas_entry_compare.h" +#include "nameserver_entry.h" +#include "nameserver_address_store.h" +#include "zone_entry.h" +#include "address_request_callback.h" + +using namespace isc::dns; +using namespace std; +using namespace boost; + +namespace isc { +namespace nsas { + +// Constructor. +// +// The LRU lists are set equal to three times the size of the respective +// hash table, on the assumption that three elements is the longest linear +// search we want to do when looking up names in the hash table. +NameserverAddressStore::NameserverAddressStore( + shared_ptr<ResolverInterface> resolver, uint32_t zonehashsize, + uint32_t nshashsize) : + zone_hash_(new HashTable<ZoneEntry>(new NsasEntryCompare<ZoneEntry>, + zonehashsize)), + nameserver_hash_(new HashTable<NameserverEntry>( + new NsasEntryCompare<NameserverEntry>, nshashsize)), + zone_lru_(new LruList<ZoneEntry>((3 * zonehashsize), + new HashDeleter<ZoneEntry>(*zone_hash_))), + nameserver_lru_(new LruList<NameserverEntry>((3 * nshashsize), + new HashDeleter<NameserverEntry>(*nameserver_hash_))), + resolver_(resolver) +{ } + +namespace { + +/* + * We use pointers here so there's no call to any copy constructor. + * It is easier for the compiler to inline it and prove that there's + * no need to copy anything. In that case, the bind should not be + * called at all to create the object, just call the function. + */ +shared_ptr<ZoneEntry> +newZone(const shared_ptr<ResolverInterface>* resolver, const string* zone, + const RRClass* class_code, + const shared_ptr<HashTable<NameserverEntry> >* ns_hash, + const shared_ptr<LruList<NameserverEntry> >* ns_lru) +{ + shared_ptr<ZoneEntry> result(new ZoneEntry(*resolver, *zone, *class_code, + *ns_hash, *ns_lru)); + return (result); +} + +} + +void +NameserverAddressStore::lookup(const string& zone, const RRClass& class_code, + shared_ptr<AddressRequestCallback> callback, AddressFamily family) +{ + pair<bool, shared_ptr<ZoneEntry> > zone_obj(zone_hash_->getOrAdd(HashKey( + zone, class_code), boost::bind(newZone, &resolver_, &zone, &class_code, + &nameserver_hash_, &nameserver_lru_))); + if (zone_obj.first) { + zone_lru_->add(zone_obj.second); + } else { + zone_lru_->touch(zone_obj.second); + } + zone_obj.second->addCallback(callback, family); +} + +} // namespace nsas +} // namespace isc |